Containers for radioactive isotopes



Dec. 17, 1963 H. c. PONTET CONTAINERS FOR RADIOACTIVE ISOTOPES 2 Sheets-Sheet 2 Filed July 25, 1960 ATTORNEYS United States Patent Ofllice Patented Dec. 17, 1963 3,11 83S CGNTAINERS FOR RADIQACTIVE EUTGPES Hermann Charles lontet, 13 Arcadian Gardens, Wood Green, London, England Filed July 25, 196i), Ser. No. 45,113 Claims priority, application Great Britain July 23, 1959 3 Claims. (til. 250-106) This invention relates to containers for housing radioactive isotopes and which are also adapted to serve as a stand for supporting them while they are being used.

Radioactive isotopes are used industrially for examining material such as metal, concrete, wood etc. by taking X-ray photographs for the purpose of detecting structural faults. For such use it is important that the isotope should be capable of being readily brought into a position of use but when not required it must be completely enclosed in a shield made of lead or other suitable material capable of preventing the escape of radioactive rays.

It is an object of this invention to provide a container comprising two parts so mounted that when in closed position they co-operate to provide a perfect ray proof housing but which are readily separated into open position to present the isotope for use.

According to the present invention a container for a radioactive isotope comprises two interengageable casings lined with lead or other suitable material, one casing being rotatably mounted and adapted to have an isotope niounter therein, the other casing being slidably mounted such that when the casings are in closed interengaged position the lead linings are in mating engagement to form a complete shield for the isotope, means being provided for moving the casings into separated or open position to expose the isotope, said means being so arranged that in their initial operation the slidably mounted casing is caused to slide away from the rotatably mounted casing and the latter is thereafter rotated into an open position wherein the isotope is exposed for use.

According to one arrangement the rotatable casing is rotated by lever mechanism including a cam engageable with an adjacent part or" the slidably mounted casing, the arrangement being such that on the initial operation or" the lever mechanism the slidably mounted casing is moved by the cam away from the rotatable casing against the action of springs and after a predetermined sliding movement has been effected, the lever mechanism is operative to rotate the rotatably mounted casing. It will be understood that the extent of the sliding movement is such as to provide suflicient clearance for the rotatable casing to be swung over the adjacent end of the slidably mounted casing.

To enable the invention to be fully understood it will now be described by way of example with reference to the accompanying drawings in which:

FIGURE 1 is a front elevation, partly in section of a radioactive isotope container according to one embodiment of the invention; and

FIGURE 2 is a side view thereof.

As shown in the accompanying drawings a frame is provided including a base 1 and laterally spaced side plates 2. A plate 3 is supported on the base by a series of vertically extending posts each comprising two telescoping tubes 4-, 5 housing coil springs 53a such that the plate 3 is capable of axial sliding movement towards the base by telescoping the tubes 4-, 5 and compressing the springs.

The radioactive isotope is adapted to be enclosed when not in use, in a two part container or shield each part being of hemispherical or like shape. One of these parts comprises a hollow casing 6 mounted in an aperture in 2 the plate 3 so as to be slidable therewith and provided with a lead lining 7. The casing d has a circular open end directed upwards. The lower end of the casing is spaced from the base 1 of the frame and has a spigot 8 slidable in an aperture in the base.

The other part of the container comprises a hollow casing 9 also having a lead lining it Part of the lead lining 1% projects from the open end of the casing 9 and is formed with a series of concentric steps 11 which, when the parts of the container are in the closed position indicated in FIGURE 1 mate with concentric steps 12 formed on the lead lining 7 of the casing 6.

The casing 9 is provided with trunnions l3 journaled in the side plates 2 of the frame. A sleeve 14 integral with the casing 9, surrounds each trunnion and a coil spring 13a is mounted in a recess in the sleeve and trunnion to serve as a resilient connection. A hand operated lever is provided including a cross bar 15 serving as a hand grip and side arms 16 which are connected to the sleeves 34.

A cam disc 17 is connected to each or" the side arms 16 for cooperative engagement with a roller 18 rotatably mounted in a bracket 19 on the plate 3.

The lead lining lid has an axial bore 20 for receiving a plug 21 having an isotope container 22 mounted in one end so as to be disposed in the centre of the open end of the lead lining. The plug 21 is adapted to be screwed into a cap 23 on the casing 9.

As indicated in FIGURE 1, when the two parts of the container are in closed position the stepped portions of the lead linings are in abutting relationship to cooperate to form a complete shield for the isotope. When the parts are in this position, the plate 3 which supports the casing 6 is urged into its uppermost or closed position by the springs associated with the telescoping tubes 4, 5 and accordingly the circular rims of the open ends of the casings 6 and 9 will be resiliently urged into sealing engagement. Further the hand operated lever will be in raised position and recessed portions 17a of the earns 17 will engage the rollers 18.

When the isotope is to be brought into a position of use a pull is applied to the cross-bar 15 to etfect the rotation of the two side arms 16. As the arms are initially rotated the cams 17 will ride over the rollers 13 and effect the downward sliding movement of the plate 3 and as the casing 6 is mounted thereon it will also be moved downwardly away from the open end of the casing 9.

When the plate 3 and casing d have been lowered into a position wherein the upper end of the casing 6 is clear of the path of rotation of the open end of the casing 9 and the projecting portion of the lead lining, abutments 2-4 on the sleeves l4 engage stops 25 on the trunnions so that the further rotation of the arms 16 rotates the casing 9. The casing 9 is adapted to be rotated through an angle of wherein its open end will be disposed in a vertical plane with the isotope disposed in the centre and facing outwards to direct its rays to the material or article to be photographed.

After use, the hand operated lever is reversely rotated to move the casin s into closed position and during the first part of the rotational movement of the casing 59, the casing 6 will be held in its lower depressed position by the cams l7 until the casing 9 is rotated into a position wherein its open end is disposed in a horizontal plane in superposed relation to the open end of the slidably mounted casing 6. The further rotation of the hand lever ettects the rotation of the cams to bring the recesses 17a over the rollers l3 and the plate 3 and casing 6 are then permitted to slide upwardly by the action of the springs associated with the telescoping tubes 5 so that the open ends of the casings are brought into abutment and the lead linings mate with one another to form a sealed housing.

It will be noted that the concentric steps of the linings form in effect a labrynth like seal to prevent the escape of radioactive rays emitted by the isotope when the container is closed.

The plug 21 is formed with axially spaced lateral shoulders 21a, 22a engageable with co-operating shoulders in the bore so that any rays from the isotope tending to pass up the bore will be scattered and deflected.

if desired means may be provided for preventing the removal of the plug 21 except when the rotatable part is in the open position. As shown a further cross bar 26 extends between the side arms 16 of the operating lever such that when the casing 9 is in closed position the cross bar overlies the top of the plug 21 making it impossible to remove the plug. When, however, the casing 9 is in open position the cross bar 26 will be displaced from the plug 21 providing free access to unscrew it to remove the isotope should this be desired.

As shown means is provided for locking the casing parts in closed position comprising a latch bolt 27 controlled by a key operated lock 28, the bolt being manually movable into a position under the spigot of the casing 6 and prevent it being moved downwardly, and being automatically retracted by the spring when the lock is operated by the key.

I claim:

1. A radioactive isotope container comprising a pair of mating elements formed of material impervious to rays emanating from a radioactive isotope, a support for said elements, means slidably supporting one of said elements on said support, means rotatably supporting the other of said elements on said support, a recessed mating surface on said slidably mounted element, a series of concentrically arranged steps of progressively decreasing diameter on the Wall of said recess, a generally dome shaped mating surface on said rotatably mounted member, a series of concentric steps on said dome shaped surface for mating engagement with the steps of said recess, an axial bore in said dome shaped surface, means for mounting a radioactive isotope in said bore, lever means for rotating said rotatably mounted member between a closed position wherein surfaces of said elements are in mating engagement, and an open position wherein said rotatable element is rotated through an angle of approximately 90, spring meansoperative when said elements are in closed position to urge said slidably mounted element towards the rotatably mounted element to effect mating engagement of said steps, cam means connected with the said lever means, abutment means connected with the slidably mounted element and engageable by said cam means, said cam means being operable on the initial operation of said lever means to impart a sliding movement to the slidably mounted element relative to the rotatably mounted element so as to effect the separation of the mating surfaces of the said elements to permit the rotatably mounted element to be rotated into said open positionby the continued operation of said lever means.

2, A radioactive isotope container comprising a pair of mating elements formed of material impervious to rays emanating from a radioactive isotope, a support for said elements, means slidably supporting one of said elements on said support, means rotatably supporting the other of said elements on said support, said slidably mounted element having a surface formed with a generally concave recess and said rotatably mounted member having a generally convex surface for mating engagement in said recess, an axial bore in said convex surface means for mounting a radioactive isotope in said bore, lever means for rotating said rotatably mounted member between a closed position wherein said surfaces of said elements are in mating engagement, and an open position wherein said rotatable element is rotated through an angle of approximately spring means operative when said elements are in closed position to urge said slidably mounted element into mating engagement with the rotatably mounted element, cam means connected with the said lever means, abutment means connected with the slidably mounted element and engageable by said cam means, said cam means being operable on the initial operation of said lever means to impart a sliding movement to the slidably mounted element relative to the rotatably mounted element so as to effect the separation of the mating surfaces of the said elements to permit the rotatably mounted element to be rotated into said open position by the continued operation of said lever means.

3. A radioactive isotope container comprising a pair of mating elements formed of material impervious to rays emanating from a radioactive istotope, a support for said elements, means slidably supporting one of said elements on said support, means rotatably supporting the other of said elements on said support to permit rotation between a closed position wherein surfaces of said elements are in mating engagement, and an open position wherein said rotatable element is rotated through an angle of approximately 90, means for mounting a radioactive isotope in said rotatably mounted element, spring means normally urging said slidably mounted element into mating engagement with the rotatably mounted element, lever means for rotating said rotatably mounted element, cam means connected with the said lever means, abutment means connected with the slidably mounted element and engageable by said cam means, said cam means being operable on the initial operation of said lever means to effect the rotation of the rotatably mounted element from closed to open position, to impart a sliding movement to the slidably mounted element relative to the rotatably mounted element so as to effect the separation of the mating surfaces of the said elements to permit the rotatably mounted element to be rotated into said open position.

References Cited in the file of this patent UNITED STATES PATENTS 2,860,255 Tumath Nov. 11, 1958 2,891,167 Coleman et al June 16, 1959 FOREIGN PATENTS 1,218,610 France May 11, 1960 

3. A RADIOACTIVE ISOTOPE CONTAINER COMPRISING A PAIR OF MATING ELEMENTS FORMED OF MATERIAL IMPERVIOUS TO RAYS EMANATING FROM A RADIOACTIVE ISTOTOPE, A SUPPORT FOR SAID ELEMENTS, MEANS SLIDABLY SUPPORTING ONE OF SAID ELEMENTS ON SAID SUPPORT, MEANS ROTATABLY SUPPORTING THE OTHER OF SAID ELEMENTS ON SAID SUPPORT TO PERMIT ROTATION BETWEEN A CLOSED POSITION WHEREIN SURFACES OF SAID ELEMENTS ARE IN MATING ENGAGEMENT, AND AN OPEN POSITION WHEREIN SAID ROTATABLE ELEMENT IS ROTATED THROUGH AN ANGLE OF APPROXIMATELY 90*, MEANS FOR MOUNTING A RADIOACTIVE ISOTOPE IN SAID ROTATABLY MOUNTED ELEMENT, SPRING MEANS NORMALLY URGING SAID SLIDABLY MOUNTED ELEMENT INTO MATING ENGAGEMENT WITH THE ROTATABLY MOUNTED ELEMENT, LEVER MEANS FOR ROTATING SAID ROTATABLY MOUNTED ELEMENT, CAM MEANS CONNECTED WITH THE SAID LEVER MEANS, ABUTMENT MEANS CONNECTED WITH THE SLIDABLY MOUNTED ELEMENT AND ENGAGEABLE BY SAID CAM MEANS, SAID CAM MEANS BEING OPERABLE ON THE INITIAL OPERATION OF SAID LEVER MEANS TO EFFECT THE ROTATION OF THE ROTATABLY MOUNTED ELEMENT FROM CLOSED TO OPEN POSITION, TO IMPART A SLIDING MOVEMENT TO THE SLIDABLY MOUNTED ELEMENT RELATIVE TO THE ROTATABLY MOUNTED ELEMENT SO AS TO EFFECT THE SEPARATION OF THE MATING SURFACES OF THE SAID ELEMENTS TO PERMIT THE ROTATABLY MOUNTED ELEMENT TO BE ROTATED INTO SAID OPEN POSITION. 